Well tool construction



July 20, 1937.

A. c. CATLAND WELL TOOL'CONSTRUCTION Filed Oct. 5, 1955 Patented July 20, 1937 UNITED STATES WELL TOOL CONSTRUCTION Alfred C. Catland, Alhambra, Calif., assignor to Globe Oil Tools Company, Los Nietos, Calif., a. corporation of California Application October 5, 1935, Serial No. 43,712

15 Claims.

This invention has to do with well drilling tools andhas particular reference to a well drilling bit construction. A general object of the present invention is to provide a well tool construction wherein the active parts or cutters of the tool from elements of a simple, inexpensive and readily replaceable unit.

In many instances deep wells such as oil wells and gas wells are located a great many miles from transportation facilities and from machine shops making it extremely diflicult, inconvenient and time consuming to replace and repair the worn parts, cutters, etc., of the well drilling tools employed in drilling the wells. l5 Another object of this invention is to provide a well bit in which all of the cutting parts or cutters are carried by-or embodied in a compact conveniently portable unit that may be easily and quickly removed and replaced by a replacement 20 unit. The cutter carrying unit of the present invention may be replaced by simple common tools at the derrick and the replacement unit is such that it may be easily transported to a well in a remote inaccessible region thus'adapting the bit for the drilling of wells in such regions.

Another object of this invention is to provide a well bit of the character mentioned in which the cutters are easily detached following the removal of the cutter carrying unit wherebythe cuttersand .their bearing parts may be individually replaced if necessary.

, Another object of this invention is to provide a well' bit of the character mentioned in which the cutters are dependably carried by the replaceable unit for eificientoperation without rendering the unit complicated or expensive of manufacture. V Another object of this invention is to provide a well bit of the character mentioned involving novel and dependable means for removably securing the detachable cutter carrier-to the shank. Another object of this invention is to provide a well bit of the character mentioned in which the cutter carrier of the'replaceable unit is simple and inexpensive of manufacture. Another object of this invention is to provide a well bit of the character mentioned that embodies a roller type well bit of the character mentioned in which the circulation fluid is discharged down- 55 .wardly adjacent the bottom of the well bore to erode the formation and thus assist in the drilling action.

The various objects and features of my inven-, tion will be fully understood from the following detailed description of a typical preferred 5 form and application of my invention, throughout which description reference is made to the accompanying drawing, in which:

Fig. 1 is a side elevation of a bit embodying the construction of the present invention witha por- 10 tion broken away to appear in central vertical cross section. j'ig. 2 is a central longitudinal detailed sectional view'of the bit taken in a plane at right angles to the plane of sectioning of Fig.

1. Fig. 3 is a bottom elevational viewof the shank with the cutter carrying unit removed. Fig. 4 is a bottom elevation of the bit showing it in the same rotative position as in Fig. 2, and Fig. 5 is a top elevational view of'the carrier of the replaceable unit removed from the shank.

The well bit provided by this invention includes generally, a shank l0 and a replaceable cutter carrying unit on the shank comprising a carrier ll removably attachedto the shank Ill,

inner cutters l2 and I3 on the carrier n and outer cutters l4 on the carrier ll. I

The shank I0 is shaped and formed to efiective- 1y receive and support the carrier I l. The shank I0 is adapted to be connected with a drilling string and is provided at its upper end with means 5 for facilitating its connection with the string. In the particular form of the invention illustrated in the drawing the connecting means is in the form of a tapered screw threaded pin l5 projecting from the upper end" of the shank. The por- 5 tion of the shank l0 immediately below the pin l5 may be cylindrical while the lower end of the shank is formed and provided with parts to receive and carry the carrier l'l. Two integral legs l6 project downwardly and outwardly from the 40 lower end of the shank Ill. The legs l6 are diametrically opposite and their inner sides are inclined downwardly and outwardly. Finished bosses or bearing surfaces H are preferably provided on the inner sides of the legs I6. In acvcordance with the invention a diametric groove or slot 18 is provided in the lower end of the shank Ill. The slot l8 may extend from one side to the other ofthe shank and its outer ends are preferably spaced substantially 90 between the diametrically opposite legs Hi. The slot l8 may have flat vertical side walls and a flat horizontal upper wall. A downwardly and outwardly inclined boss or stud l9 projects from the upper wall of the slot l8 adjacent one end of the slot. 5

' The boss or stud I3 is preferably integral with the shank it.

The cutter carrying unit of the hit is an important element or feature of the invention.

The unit carriesor embodies all of the cutters of the bit and is such that it may be easily and quicklyureplaced whereby the bit may be readily reconditioned forfurther use after its original cutters, etc. have become worn. The replaceable cutter carrying unit is relatively compact so that it may be transported or shipped to remote regions to recondition a worn bit. The carrier H which forms'the body or principal element of the replaceable cutter carrying unit is an ina be hereinafter described.

tegral spider-like member adapted to be attached to the lower end of the shank L The carrier It includes an elongate transversely or horizontally extending part 20 of substantially rectangular cross section adapted to fit in and cooperate with the slot l8. The upper surface of thepart 23 is adapted to cooperate with the upper wall of the slot |8 to, receive the downward pressures from v the shank while the opposite sides of the part 20 cooperate with the side walls ,of the slot to rerelative to the stud I9.

. stud 'ceive the rotative or turning thrusts from the Three. integral projections A, B and C project downwardly from the part 2|! and constitute cutter carrying parts of the carrier The projection A is adjacent and at one side of the central vertical axis of the bit, the projection B is spaced outwardly from the projection A at the same side of the said axis, while the projection C is spaced outwardly from the projection A and is disposed at the opposite side of the said axis from the projections A and B. The projection C is relatively thick'andhas a downwardly and outwardly inclined opening 2| for receiving the IS. A, notch 60 having downwardly and outwardly inclined walls is provided in the lower end of the inner projection A. Integral legs or -portions presenting outwardly facing surfaces 24 which are substantially parallel with the surfaces ll of the legs l6. 'Ihe inner sides ofthe wings 22. are inclined and form the walls of the notch Cylindrical bearing studs or pins 25project upwardly and outwardly from the surfaces 24 at right angles thereto and their outer ends are adapted to bear on the surfaces ll of the legs IS. The pins 25 are preferably integral with the bosses 23.

The invention provides novel dependable means for removably attaching the carrier II to the shank l0. Integral lugs 26 project laterally from opposite sides of the carrier part- 24 to bear against or be adjacent the lower end of the shank Ill. The. lugs 26 are located at the opposite side of the central vertical axis of the bit 7 Studs or screws 21 are passed through openings in the lugs 26 and are threaded into openings 23 in the lower end of the shank III to attach or assist in securing the ter l2.

The means for removably attaching the carrier tothe shank l0 includes in addition to the screws 21 and the member 30 studs or screws 34 passed through longitudinal openings 35 in the bearingpins 25 and threaded into openings 36 in the legs IS. The heads of the screws 34 are counter-sunk in the inner sides of the bosses 23 and the threaded outer ends of the screws 34 may be peened at the outer sides of the legs I6 to lock the screws 34 against unthreading. The screws 21 and 34 and the member 30 securely and dependably' attach the cutter'carrier I I to the shank I. It is tobe noted that the screws Hand 34 and the member 30 may be easily engaged and turned by simple common tools.

The inner cutters l2 and I3 are carried by the carrier II to act on the inner portion of the bottom wall of the .well bore. The cutters l2 and I3 are frusto-conical roller cutters having inclined peripheries provided with cutting parts or teeth 3|. Each cutter l2 and I3 has a central longitudinal opening 38. The cutter I2 is supported for rotation between the projection A and the projection C to act on the formation at or adjacent the center of the bottom wall of the well bore whilethe cutter I3 is supported for rotation between the projection A and the projection B to have a path of action on the formation surrounding and overlapping the path of the cut- .In accordance with the invention a single removable means or member rotatably supports the two cutters ILand |3. A pin 39 is passed through a substantially horizontal opening 40 in the pro jection B and is threaded into an opening 4| in the lower portion of the projection C. The pin 39 passes through the openings 38 in the cutters l2 and J3 and roller bearings 42 may be provided inthe openings 38 to support the cutters on the pin. The opening 4| joins the opening l9. and the inner end of the pin 39 may be grooved or shaped for engagement by the member 30 whereby the member holds the pin against turning. Thus the member 30 operates as alock member to prevent displacement-of the pin 39. A thrust washer43 is arranged on the pin 39 between the outer end of the cutter l3 and the inner surface,

of the projection B, The washer 43 has shouldered engagement with the projection B at 44 which holds it against rotation. The pin 39 extends through the notch 60 and a spacer '45 is arranged on the pin to properly space the two cutters 2 and I3. The spacer 45 preferably has clearance with the walls of the notch 60. With this construction it is unnecessary to provide an opening in the projection A which is aligned with carrier II to the shank. The opening 2| in the c" rrier receiving the stud I9 enters the pro* jection C from itslower end and has a downwardly facing shoulder .29 on its wall spaced above the'lower end of the stud IS. A member 30 passed into the lower end of the opening .1.

2| and is threaded on the stud l9 to bear upwardly against the shoulder '29 and thus assist in attaching the carrier to the shank II. A

polygonal socket 3| in the lower end of the memthe openings 40 and 4| and it is not necessary to accurately finish the ower end of the projection A. The frusto-conical ner cutters I2 and I3 are rotatably supported on the pin 39 to have their" smallest ends facing inwardly or toward the central vertical axis of the bit. The cutte s l2 and' The ,outer cutters I4 are providedvto act on the outer portion of the well bore and trim or ream the wellto gauge- The cutters I4 are substantially frusto-conicalhaving inclined peripheries provided with cutting parts or teeth 5. The teeth 5 are preferably spiralled and the teeth of one cutter I2 may be spiralled in a right-hand direction while the teeth of the other cutter may be spiralled in a lefthand direction sothat the teeth of the two cutters cannot track in their engagement with the earth formation. The outer roller cutters I4 are rotatably supported on the bearing pins between the bosses 23 and the legs I6 to rotate about downwardly and inwardly inclined axes- Roller bearings 46 may rotatably mount the cutters I4 on the bearin pins 25. Thrust washers 41 are provided on the pins 34 at theouter ends of the cutters I4. to

bear on the surfaces-I1 of the legs I6. The washers 41 have shouldered engagement with the legs I6 at 48, which engagement holdsthem against turning. The outer corners 49 of the teeth 5 are preferably bevelled to be substantially vertical as they come into engagement with the formation at the bottom of the well.

The invention provides means for flushing the cuttersl2, I3 and I4 and for directing a stream of circulation fluid against the bottom of the well.

A socket or opening 50 enters the shank II) from wardly against the cutter I3. A port 55 extends downwardly from the lower end of the opening 50 and a replaceable choke 56 is threaded in the lower end of the port 55 to project from the upper wall of the slot I6. 'An opening 51 in the carrier part 20 receives or passes the choke 56 so that the choke is adapted to discharge a stream of circulation fluid downwardly against the inner cutters I2. The openings 55 and 55 are shaped to readily receive the chokes 53 and. 56 when the carrier II is arranged'on the shank III to have its opening 2i receive the inclined stud I9.

'In accordance with the invention a downwardly and outwardly inclined port 58 extends through the shank I0 from the opening 50 and continues longitudinally through the stud I9. The member 35 is'tubular having a longitudinal opening 59 whose upper end communicates with the port 58. The opening .59 is adapted to discharge circulation fluid downwardly and outwardly through the polygonal socket 3| so that the member operates as a nozzle or choke. The circulation fluid issuing from the opening 59 discharges downwardly and outwardly adjacent the side wall of the well bore to assist in the drilling action and to provide a desirable turbulence in the lower portion of the well.

In operation of the bit the shank I6 is connected with the lower end of the drilling string and the bit is operated on the lower end of the string in the'usual manner. As the bit is rotated and fed downwardly the inner cutters I2 and I3 act on and cut away the formation in the central portion of the bottom wall of the bore while the outer cutters I4 act on and cut away the formation at the outer portion of the bore and cut the bore to gauge. The cutters I2, I3 and Marc positioned so that the bit is well balanced and has active engagement with the entire bottom wall of the well during eachcomplete revolution. The circulation fluid pumped downwardly through the flush and clean the outer cutters I4 and dis-v drilling string discharges from the ports 5| .to

charges from the chokes 56 and353 to flush the' inner cutters I2 and I3. A stream of circulation fluid under pressure is also discharged from the opening 59 and socket 3I of the member 36. This stream of fluid is discharged downwardly and outwardly adjacent the side wall of the Well toassist in the drilling operation and to maintain an effective turbulence. The'walls of the slot I8 cooperate with the part 26 of the carrier II to transmit the downward pressures and the turning forces to the carrier so that the stud I9, the screws 21 and 34 and the chokes 53 and 56 are not subjected to these forces. The screws 21 and 34 and the member 30 hold the part 20 of the carrier II in the slot I8 and positively prevent displace ment of the carrier from the shank. The member 30 is locked against displacement by the pin 32 and the member 36 operates to lock the screw 39 against unthreading. The cutters I2, I3 and I4 are supported for free independent rotation.

When the cutters have become worn the care rier'II may be easily and quickly detached from the shank I 0 by simple tools. The' screws 21 and 34 and the member 36 are easily unthreaded to permit the detachment of the carrier II from the shank. The chokes 53 and 56 are also easily removed for replacement when worn. If desired or found necessary the carrier II may be replaced by a new or replacement carrier having new cutters I2, I 3 and I4. The cutters I2, I3

and I4 are mounted on the carrier II so that they may be easily and quickly detached from the carrier for independent replacement when worn or broken. The carrier II is compact and easy to transport adapting the bit for employment in the drilling of wells in remote inaccessible regions. The carrier -I I is a simple, integral part and the shank I0 is a one-piece member that is inexpensive to manufacture.

Having described only a typical preferred form and application of my invention I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art or fall within-the scope of the following claims.

Having described my invention, I claim:

1. A well bit including a shank having a polygonal opening, and a replaceable cutter unit comprising a plurality of roller cutters, a carrier supporting the cutters for operation having a polygonal part fitting said opening whereby. the carrier turnswith the shank, and means removably connecting the carrier to the shank to retain the said part in the opening, there being a port spaced wings projecting downwardly from the carrier, pins projecting from-the wings toward the legs, outer cutters rotatable on the pins,

spaced projections on the lower end of the'carrotatable on said pin at opposite sides of the central 'longitudinalaxis of the bit.

' 3. A well bit including a shank having spaced depending legs, and a replaceable unit comprising a carrier detachably connectedto the shank, spaced wings -on the carrier opposing the legs, bearingjpinson the wings, screwsty'ing the pins to the legs, outer cutters rotatable on th'e bearing pins, spaced projections on the carrier, 3. pin

passing between the wings without bearing on the' rotatableon-the pins, spaced projections on the the wings and carried by the projections, and

inner cutters rotatably supported on the pin.

5. A cutter unit for a well bit comprising a carrier having two spaced upwardly and outwardly projecting pinsand spaced downwardly projecting projections spaced from the pins, cutters rotatable on the pins, bearing pin passing transversely between said pins andsupported by the projections, and cutters on the bearing pin.

6. A cutter unit for a well bit comprising an integral carrier including depending wings havingoutwardly projecting pins, and spaced depending projections spaced from the pins, apin passing-transversely between'the wings and supported on the projections, and roller cutters rotatable on the pins.

7. A cutter unit fora well bit comprising an integral carrier including depending wings hav-' ing outwardly projecting pins, and spaced depending projections, a pin passing between the wings and supported on the projections, outer on the said pin, and a spacer carried by the pin between the said cutters and located'between the Wings.

- -8. A cutter unit for a well bit comprising an carrier, a ,pin extending between and carried by the projections, and rotatable cutters on the pin flushed by fluid discharged from the members.

11. A well bit including a shank having fluid ports, discharge members communicating with' the-ports and projecting from the lower end of the shank, a removable carrier on the lower end of the shank having openings receiving the discharge members, and roller cutters carriedby the carrier where they are flushed by fluid from the members. Y

12. A well bit including a shank having .fluid ports, discharge members communicating with the ports and projecting from the lower end 0! the shank, a removable carrier on the lower end of the shank having openings receiving the discharge members, projections on the 'carrier, a removable pin extending between and carried by the projections, a part threaded on one of said members andholding the pin against displacement, and a roller cutter rotatable on the pin.

13. A well bit including a shank having fluid ports, discharge members communicating with the ports and projecting from thelower end of the shank, a. removable carrier on the lower end of. the shank having openings receiving the dis- .14. A, well bit including a shank having fluid ports, discharge members communicating with integral carrler'including depending wings hav- 'ing outwardly projecting pins, and spaced depending projections, a pin passing between the adapted to or an openingin' the 1m shank, de-.

p d n w nes havinl outwardly p oie ne p s.

- and spaced depending projections. a pin passing as between the wings and mpported m the projections, and roller rotatable on the pins.

for a well blt comprising an.

the ports and projecting from the lower end of the shank, a removable carrier on the lower end of the shank having openings receiving the discharge members, projections on the carrier, a removable pin extending between and carried by the projections, a part threaded on one of said members to discharge the circulation-fluid and -holding the pin against displacement, and a roller cutter rotatable on the pin.

A well bit includingashank having fluid ports, discharge members connnunicating with ---the ports and projecting from the lower end of the shank, a removable carrier on the lower end of the shank having openings receiving the discharge members a removable pin [on the-carrier, a rotatable. cutter on the pin flushed by fluid discharged from one of said members, and a tubular part threaded on the other memberto discharge the fluid and operating to connect the carrier to the shank and prevent displacementof the pin.

ALFRED C. CATLAND. 

